My cat-human hybrid I'm making needs a right ear and it needs to be mirrored.
Well, if you don't want to use a Mirror Modifier, you could nevertheless use it and apply it afterwards by pressing "Apply" after you're done modeling.
Or you go into Edit Mode, delete half of your mesh (depends on which axis you want to mirror, in this case I guess it's the X-Axis), then press W and select "Symetrice". There are different options when you open up the toolbar (T), so play around with the axis mirror type.
Attention: Be sure that the origin of your model is located at the cutting edge, otherwise it will cut it where the origin is located at. To move the origin, select the cutting edge in Edit Mode, press Shift + S, select "Cursor to Selection", the go into Object mode, select your mesh and press Ctrl + Shift + Alt + C and select "Origin to 3D Cursor". And make sure to apply any rotation or scale changes before doing so.
This works both in Object and in Edit mode.
- Place the 3D cursor where the mirror axis origin would be (Shit+C will place it at position (0, 0, 0)
- Change Pivot center for rotation or scaling to be 3D cursor (or press . (dot) on the keyboard)
- Duplicate the object or part of mesh you want to mirror (Shift+D)
- Press Ctrl+M (or find command Object->Mirror Mesh->Mirror) and then select the axis you want to mirror the duplicated object along (in interactive mode press X, Y or Z on the keyboard). Click left mouse button to confirm.
In order mirroring to work correctly in Object Mode you have to Apply Scale and Rotation on the object first.